Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux...

[karo-tx-linux.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index be197f71b096cb83d6ac48ab68cef84b2ba3fc61..d99664e8607e761235a13b2662353df131ac5b41 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1149,6 +1149,13 @@ int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
 EXPORT_SYMBOL(redirty_page_for_writepage);
 
 /*
+ * Dirty a page.
+ *
+ * For pages with a mapping this should be done under the page lock
+ * for the benefit of asynchronous memory errors who prefer a consistent
+ * dirty state. This rule can be broken in some special cases,
+ * but should be better not to.
+ *
  * If the mapping doesn't provide a set_page_dirty a_op, then
  * just fall through and assume that it wants buffer_heads.
  */